The periodic table of chemical elements, often called the periodic table, organizes all discovered chemical elements in rows (called periods) and columns (called groups) according to increasing atomic ...

As you move from left to right across the periodic ... charge) and electrons, pulls the electrons closer together, hence the smaller size. As you move down a group in the periodic table, the ...

But how many of these elements do you know? Test your knowledge and compete with other Live Science readers to see who can ...